Look, simply because NT people are a lot better at gauging impressions, doesn't mean we should subscribe to hyperbole like "NT's could care less about the truth, they only protect their egos" (which is more a consideration of culture than anything else, and not really an observation of cognitive differences per se) or that they somehow have a very specific understanding of the other person's mental state during these interactions.
Your NT friend probably has no idea either whether or not he worked there, etc. What she was able to ascertain was his agitation, and she would probably be able to guess at some reasonable explanations why. NT's don't communicate minute details in conversation that necessarily lead to complete abstract thoughts. There is nothing empirical about it. What they can communicate easier is impressions, moods, and so on. There is a cacophony of reasons he might have been irritated with you. One reason you could consider is that he wasn't irritated with the words you said to him, but rather he was irritated at your tone of voice, your manner or posture, or something else of that nature.
Also, your NT friend is no prophet or mind reader either. Simply because he gave her that impression doesn't instantly mean he was irritated, and even if he was it may not have been you that irritated him. He may have been irritated by something else already, and expressed this to you with his tone of voice and facial expressions either involuntarily, or as an indication that because he is already predisposed to be irritated he doesn't feel like conversing with you at the moment.
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There is no wealth like knowledge, no poverty like ignorance.
Nahj ul-Balāgha by Ali bin Abu-Talib